John J. Leddy, MD Clinical Professor Department of Orthopaedics Jacobs School of Medicine & Biomedical Sciences University of Buffalo

Sport-Related Concussion: Sub-threshold Exercise May Speed Recory Interview with:

John J. Leddy, MD Clinical Professor Department of Orthopaedics Jacobs School of Medicine & Biomedical Sciences University of Buffalo

Dr. Leddy

John J. Leddy, MD
Clinical Professor
Department of Orthopaedics
Jacobs School of Medicine & Biomedical Sciences
University of Buffalo What is the background for this study?

Response: Sport-related concussion (SRC) is a significant public health problem without an effective treatment. Recent International Guidelines have questioned the efficacy of recommending complete rest to treat concussion and have called for prospective studies to evaluate early active treatments for sport-related concussion. What are the main findings?

Response: In this randomized clinical trial (RCT), male and female adolescent athletes (aged 13-18 years) presenting within 10 days of SRC were randomly assigned to aerobic exercise (n=52, 46% female) or to placebo stretching program (n=51, 47% female). Those assigned to aerobic exercise recovered faster (13 days) compared with those assigned to a placebo-like stretching program (17 days), a significant difference. There was a non-statistically significant lower incidence of delayed recovery (defined as requiring more than 30 days to recover) in the aerobic exercise group (2 aerobic vs.7 placebo stretching participants, p= 0.076). There were no adverse effects of early controlled aerobic exercise treatment prescribed after SRC. What should readers take away from your report?

Response: This is the first RCT to show that individualized sub-symptom threshold aerobic exercise treatment prescribed to symptomatic adolescents during the first week after Sport-related concussion speeds recovery and may reduce the incidence of delayed recovery. Moderate levels of daily physical activity instituted within a week of  sport-related concussion that do not exceed the individual’s symptom-exacerbation threshold are safe and are more effective than rest for helping adolescents recover from sport-related concussion. What recommendations do you have for future research as a result of this work?

Response: The results need to be replicated in a larger sample from more centers using an intent-to-treat study design. A larger sample would allow for determining potential sex and race-related differences in the effect of early controlled exercise on recovery from SRC in adolescents and more definitively establish that early intervention helps reduce the incidence of delayed recovery. The sample ideally would also include those with depression and ADHD and attempt to quantify the amount of exercise performed by participants with objective measures. Is there anything else you would like to add?

Response: The results of this study should give treating clinicians confidence that levels of physical activity that do not increase symptoms are safe and are more effective in treating adolescents with sport-related concussion early after injury, even when they are symptomatic, than advising complete rest from all physical and cognitive activities until all of their symptoms resolve.

Any disclosures? The study was completed with the support of the University at Buffalo Clinical Translational Research Center and the National Institutes of Health. 


Leddy JJ, Haider MN, Ellis MJ, et al. Early Subthreshold Aerobic Exercise for Sport-Related ConcussionA Randomized Clinical TrialJAMA Pediatr. Published online February 04, 2019. doi:10.1001/jamapediatrics.2018.4397 

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Last Updated on February 7, 2019 by Marie Benz MD FAAD